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Steering shaft Thread

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Zitch

Zitch

Jedi Hopeful
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I was replacing my steering wheel and repairing my horn this weekend, I got the nut off but could not get it back on.


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Do you think I will be able to repair this thread? Anyone know the size of the thread? I think it's 28 TPI from what I read in another post search. Looks like the steering shaft is NLA for this model (63 TR4). Guess I could always rethread to smaller size but I really don't want to do that.

Guess I'll start with some new nut and try to find a Die that size. Anyone ever used a thead repair tool like this?
app01.jpg


I think they only go to 1/2" that might not be big enough for the steering shaft.
 
The only way I know to fix a stripped thread is to weld it large and re-cut it to the proper thread. You cann research smaller sizes to retread down to...but a new shaft may be in order (new used, that is).
 
Zitch said:
Do you think I will be able to repair this thread? Anyone know the size of the thread? I think it's 28 TPI from what I read in another post search. Looks like the steering shaft is NLA for this model (63 TR4). Guess I could always rethread to smaller size but I really don't want to do that.

Guess I'll start with some new nut and try to find a Die that size. Anyone ever used a thead repair tool like this?
app01.jpg


I think they only go to 1/2" that might not be big enough for the steering shaft.
Click to expand...

I forget the size offhand, but it is a "special", not a standard thread. You're not likely to find a die that fits, and if you do it will be very expensive. However, tools like the one you pictured are available in larger sizes, so that might be a way to go.

When you say the nut wouldn't start, do you mean it slipped down over the end of the shaft and wouldn't grab? Or wouldn't thread over the end of the shaft?

One solution, tho not necessarily the best or most practical, would be to have a friend with a lathe machine a nut with the same pitch but a slightly smaller inner diameter. Then machine some slots through the threads, so it will also act like a die and cut it's own threads. This was a common trick for "repairing" threads in carb inlets and oil pan drains (although they used plugs with oversize threads instead of nuts with undersize).
 
From your picture, I'd guess the nut you took off was the wrong thread. If you get a different shaft, be sure you get a matching nut with it.
 
I was able to turn the nut about a full turn till it get to the clean threads, and then it seems to cross thread.

How hard is it to remove the shaft?
 
I've always had good luck using thread files for repairs such as that. They are available in many sizes, and are reasonably priced. They come in standard sizes and metric. It's worth having three or four of these files on hand when problems like this crop up.

With the proper size file, you won't have to remove the shaft. If you have a thread gauge, then you can see what size they are...that's another item that's handy to have in the tool box.

https://www.amazon.com/KD-Tools-Thread-Restorer-Sizes/dp/B000VXIXUK

 
Did the nut come off easy or did it come off hard like it was cross threaded or the wrong size? sometimes you can use the nut to cut the threads back to normal, although if it messed them up coming off it may be the wrong size as others have speculated, you can get a new nut from the usual suspects, and maybe it could re-thread the shaft for you.
 
There is something strange about this particular nut/thread. I've had problems putting the nut back on the threaded shaft even with no apparent damage to the thread. I have a number of other shafts/nuts and usually go fishing for one that seems to go on smoothly. Often, I don't find one. I've taken to heating the nut and then putting it on the shaft. It goes on more easily but I'm not sure why I have to do this. It comes off smooth! Go figure.
 
I measured the shaft and it appears to be .552"X27 tpi. Seems a little small for 9/16". Travers Tool has special dies and lists a 9/16x27 for $28.28 plus shipping. I would try the thread file first to restore the starting thread. If no joy, remove the shaft and replace it (should be same as TR6?) or chuck the shaft in a lathe, pickup the thread and re cut the starting thread. The thread repair tool shown in the photo was listed as "not available", but maybe another source has it. Maybe you could borrow one from a machine shop. Lots of options.
Berry
 
I had that when I first started on my car back in the early 80s. I got a friend to turn new threads and used a smaller nut. Years later when I got a parts car I replaced it with a used one that was undamaged. That nut is a bastard size, but from the looks of the shaft I would think you could file it.

Dan B.
 
titanic said:
I measured the shaft and it appears to be .552"X27 tpi. Seems a little small for 9/16".
Click to expand...
A little small, but only a little. 9/16 is .5625 and normal SAE thread form means the threaded portion measures smaller than the nominal diameter by 1/4 of the thread pitch (about .009" for 27 tpi).
Travers Tool has special dies and lists a 9/16x27 for $28.28 plus shipping.
Click to expand...
I must not know how to work their web site, as I couldn't find a 9/16-27 die. All I found were taps.

But from what I can see in the photo, the last few threads are rolled over and distorted; there is a discontinuity in pitch between them and the undamaged threads. As someone said, looks like a nut with the wrong pitch was forced on. Running a cutting die up that is not likely to end well.
 
Randall-The die is on page 191 with the "special dies", item 17-036-273. I agree that the die might not be the best fix. If the shaft is the same as the TR6 one, there should be a lot of the out there and would probably be cheaper than going to a machine shop. If a friend with a lathe was available, I would try that option, after attempting the thread file.
Berry
 
Went to visit Marv last week...if he don't have it, you don't need it! I plan to visit many times in the future!
 
titanic said:
Randall-The die is on page 191 with the "special dies", item 17-036-273.
Click to expand...
And it is on the web site; just doesn't come up in the search results. Strange.
 
I find most of the web catalogs are kind of clumsy to navigate, probably a good excuse to request a paper one. In thinking about single pointing the threads on a lathe, I noticed that 27 tpi is not shown on the thread cutting chart of my lathe (Jet). I have often wondered why.
Berry
 
titanic said:
I noticed that 27 tpi is not shown on the thread cutting chart of my lathe (Jet). I have often wondered why.
Click to expand...
Probably takes special gears to get 27 tpi (which is an uncommon pitch). I don't think the quick change on my old Atlas will do them either, even though it has something like 50 different pitches. Here's a page I just found that might help
https://www.chaski.org/homemachinist/viewtopic.php?t=81298
 
titanic said:
I find most of the web catalogs are kind of clumsy to navigate, probably a good excuse to request a paper one.
Click to expand...
That's one of the things I really like about McMaster-Carr; their web site is a joy to use. Much easier than the printed catalog, IMO (which must weigh over 20 pounds and run close to 4000 pages by now).

But they want $66 for the 9/16-27 die. Definitely not the cheapest place around.
 
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